Piston-packing expander.



GERGE CHRISTENSON, 0F JAMAICA, NEW YORK, ASSIGNOIR T0 H. W. JOHNS-MANVIILLE COMPANY, A CORPORATION OF NEW YORK.

PSTON-PACKING EXPANDER.

ggggqgg, spcieaiion @i teneis raient. P'mnmd Apro an, 3193i ein Application filed August 21, 196. Serial No. 116,095.

To all whom t may concern.'

Be it known that I, GEORGE Ci-inisTnNsoN, a citizen of the United States of America, residing at Jainaica, county of Queens, State of New York, have invented certain new and useful Improvements in Piston-Packing Expanders, of which the following is a specification.

My invention relates to devices for eX- nient. The concave or inner grooved side 13, of the ring ll, is of a cross section suiiicient to encompass the two spring split-rings l5, l5, placed on either side of the piston iollower tongue 14.

In operation, the spring split-rings 15, 15, tend to expand and to force the packing ring ll, which is preferably of softer, cheaper panding iexible packing for pistons such as brake cylinders, and coininproveincnts on, or inodiiistructure shown in iny U. S.. ,540, dated Aug. 6, 190?. The paratus embodying' niy presow known to ine is illustrated anying sheet of drawings in are used in air prises certain i cations of, the Patent NoSGQ best forni of a ent invention n in the accoinp which- Figure l is an axial cylinder and plied thereto,

piston with iny invention apparts heingvbroken away and Fig. 2 is a perspective view of the channeled splitting expander.

Throughout the drawings like reference oi the cylinder. A tongue le, on the pis The advantages o prior forms of pist comprise the broad i sure exerted on the packing leather section of an air brake pressure resulting f spring split-rings l5,

metal, against the inner portion of the cylindrical section Si, packing and hold it iirinly against the walls of the cup leather t the saine tiine the ton structure serves as a guide and retainer for the composite packing ring expander formed by the parts l1,

f niy invention over on packing expander irea of outward pres inner surface of the resulting from the wide face of ring ll, the even character of that rom the use of two l5, one pressing along .on the inside. Preferably the ends of this characters indicate like parts. 1, is a portion of the ordinary air brake cylinder hav- Y ing the head 2, fastened to it by bolts 3. 4, is a piston head, 5 the piston follower, and 6, one of the bolts which fasten the head and follower together to forni the usual piston structure. 7, is the usual forni of liol low piston rod used in freight brake equipment, set in the piston head 4, and 8, the usual push. rod. The usual forni of cup leather packing shown in Fig. l orined oit' strip oi leather or other ileXib nia- 'teiial having the cylindrical outer portion 9, and the inwardly bent ring-sliaped inner edge portion l0. ,f

v The foregoing parts are of usual. construe tion except that the piston follower 5, iscut away more than usual so 4as to leave a` circumferential tongue lf, projecting therefrom. ll, is a split-ring shown in perspective iii Fig. 2, which is of channeled cross section with the concave or channel portion each edge of ring ll, and the location of the pressure surface solely against the cylindrical portion 9, of the cup leather and up to the extreme edge thereof. These features of operation or" inypresent invention avoid the tendency of packing leathers to curl hack at the edge, and to wear through at 'the junction oi' portions 9, and l0, as the result of the pressure of the expander being local` ized at that point in most previous struc tures. The use oi'f two springs also gives flexibility and insures the automatic adjustnient of the structure to any inequalities in the thickness oi' the packing leather.

.Having described my, invention, l claim: l. The combination with the usual piston structure and band of ilerihle packing there on of a split-ring, of channeled cross section arranged within said paclr'ng and two spring split-riiigs mounted in the inner constructure having a radially projecting guide extending between said spring rings.

2. The combination with the usual piston ring are tongued` and grooved as shown at i2. to' maintain the abutting ends in aline` having its concave side toward the center cave side of the channeled rino', the piston Mmmm 'l uower unil iup leather packing nel' ed Jed baween the ptafng cf channeled Somme inward y V the cylindrical G' A upackng zu -wo spring-splitwmec within im mentionee ring, said piston follower having a circumferentia tonfme of proper cross section to t between le two spring-rings and said tongue and spring-rings filling the inner concave portion of the first mentioned ring when the parts are assembled.

GEORGE CHRISTENSON. 

